The present invention relates generally to switches, specifically to switches actuable by touch, more specifically to membrane switches, and more particularly to membrane keyboard apparatus.
Increased interest in electronic apparatus having switch keyboards, such as calculators, typewriters, and similar apparatus, has increased the need for keyboard apparatus. Such keyboard apparatus should include a minimum number of components which can be easily manufactured and which lend themselves to mass production techniques thus reducing the cost of materials and labor.
Such keyboard apparatus should also include a membrane member having height differential obtaining means for electrically insulating at least one electrode member of the electrode members of an individual switching unit such that further insulator means between the membrane and electrode members of the individual switching unit are not required.